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The unpredictable Australian bowed for the crowd after an impressive backhand stab volley gave him a 4-2 lead in the second set but he was otherwise business-like in the win.
Kyrgios, who won the Citi Open at the start of the month, said he was ready to build on that success after he was eliminated in the first round of the Rogers Cup on Tuesday following an argument with the chair umpire.
"I'm super happy with that week but I'm trying to build on it," Kyrgios said of winning the title in Washington.
"It was an amazing week, awesome memories. I'm trying to create more things like that."
Next up for Kyrgios is a first career meeting with eighth seed Karen Khachanov in the second round on Wednesday.
Earlier, Marin Cilic became the first seed to fall when he was eliminated by Radu Albot of Moldova 6-4 7-6(6), while Serbia's Miomir Kecmanovic upset Canadian Felix Auger Aliassime 6-3 6-3.
American Sam Querrey and Japan's Yoshihito Nishioka were also winners, Querrey outlasting France's Pierre-Hughues Herbert 7-6(2) 7-6(1) and Nishioka defeated Australian Jordan Thompson 7-5 5-7 6-4.
Chris Froome (Stage 3, 2015)